Best Blood Test for Women's Hormones (UK)

Female hormones shift constantly: across the menstrual cycle, through perimenopause, after pregnancy, with hormonal contraception. A blood test, taken at the right time, can clarify what is going on. This guide explains what to test, when in your cycle, and which Chxhealth panels apply to common scenarios.

Core hormones for women

FSH and LH: Follicle stimulating hormone and luteinising hormone drive the menstrual cycle. Both are typically tested on day 3 of the cycle (counting from first day of period).

Oestradiol (E2): The main form of oestrogen, also tested on day 3 for cycle reference.

Progesterone: Best tested on day 21 of a 28-day cycle (or 7 days before your expected next period) to confirm ovulation.

Testosterone and SHBG: Relevant for PCOS, acne, hirsutism and low libido.

Thyroid (TSH, free T4, free T3): Thyroid issues are several times more common in women than men.

AMH (Anti-Müllerian Hormone): Marker of ovarian reserve, useful when fertility planning. Can be tested any day of cycle.

When in the cycle should you test?

Day 3 (early follicular): FSH, LH, oestradiol — gives baseline reproductive hormone status.

Day 21 (or 7 days before expected period): Progesterone — confirms ovulation has occurred.

Any day: AMH, thyroid, testosterone, SHBG, prolactin.

If your cycle is irregular or you are postmenopausal, testing can usually be done on any day, but bring a note of the date so the report can be interpreted in context.

Hormonal contraception

If you are on the combined pill, mini-pill, implant, injection or hormonal IUD, your hormone readings will reflect the synthetic hormones in your system rather than your natural baseline. If you want a true baseline, allow your cycle to return after stopping (typically 2 to 3 months) before testing. Use an alternative form of contraception in the meantime if you are not planning to conceive.

Best Chxhealth panels for this

The Chxhealth panels below are designed for the markers discussed above. Each comes with a plain English PDF report, lab analysis by Randox (UKAS, ISO 15189), and the phlebotomy fee included in the price.

Related biomarker guides

Read more about the specific markers discussed in this guide:

• Oestradiol
• Progesterone
• AMH
• TSH
• Free T4
• Testosterone
• SHBG

FAQs

Can I take a hormone test on hormonal contraception?

Yes, but the results will reflect the contraceptive hormones rather than your natural levels. For a baseline, test 2 to 3 months after stopping.

What if I do not know which day of my cycle I am on?

Many panels can be taken on any day if cycle timing is unknown. Note your last period start date on the booking form and the report will be interpreted in context.

Do I need to fast?

Fasting is not strictly required for hormone tests. If you are also testing lipids or glucose alongside, fast for 10 to 12 hours.

Can the test diagnose PCOS or menopause?

No. Chxhealth is a biomarker and genetic data provider. We do not diagnose, treat or prescribe. Our service supports your wellbeing journey alongside your healthcare professional. Blood tests provide data that supports a clinical diagnosis, which must be made by a qualified clinician based on symptoms, tests and clinical history.

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About this guide. Educational content for general awareness. Chxhealth is a biomarker and genetic data provider. We do not diagnose, treat or prescribe. Our service supports your wellbeing journey alongside your healthcare professional. For medical advice about your health or results, please speak to a qualified clinician.